cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A339945 Numbers y such that sqrt(6*y^2+10)-3 is prime.

Original entry on oeis.org

3, 13, 31, 129, 29180479, 121378881, 110778874246369293, 263631110418336671, 95129083120198558843838970225921, 213007829848951141529011991896053267187
Offset: 1

Views

Author

J. M. Bergot and Robert Israel, Dec 23 2020

Keywords

Comments

sqrt(p + (p^2-1)/6) for p in A339935.
Primes in this sequence include 3, 13, 31. Are there any others?

Examples

			a(3) = 31 is a term because sqrt(6*31^2+10)-3 = 73 is prime.
		

Crossrefs

Cf. A339935.

Programs

  • Maple
    g:= gfun:-rectoproc({a(i+4)-10*a(i+2)+a(i)=0, a(0)=1, a(1)=3, a(2)=13, a(3)= 31},a(i),remember):
    select(y -> isprime(sqrt(6*y^2+10)-3), map(g, [$1..100]));
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